Valve seat cutting device



Aug. 22, 1933a F. w. SEELERT VALVE SEAT CUTTING DEVICE Filed May 31,1930 Patented Aug. 22, 1933 UNITED STATES PATENT OFICE VALVE SEATCUTTING DEVICE Frederick W. Seelert, Minneapolis, Minn.

Application May 31, 1930. Serial No. 458,195 2 Claims. (Cl. 90-125) Mypresent invention relates to a novel and extremely accurate valve seatcutting device and has for its main object the provision of such adevice in which the cutting element may be accurately positioned beforethe cutting operation is commenced and maintained in that presetposition during the entire cutting operation.

Generally stated, the invention consists of the novel devices andcombinations of devices hereinafter described and defined in the claims.

In the accompanying drawing, which illustrates the invention, likecharacters indicate like parts throughout the several views.

Referring to the drawing:

Fig. 1 is a plan view of the device showing the same in operativeposition on a motor block, which block is indicated onlydiagrammatically and some parts thereof being broken away;

Fig. 2 is a View in axial section taken on the line 2-2 of Fig. 1 andshowing the same in operative position on the motor block, some partsbeing broken away;

Fig. 3 is a view of the device in side elevation on a reduced scale;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a view taken on the line 5-5 of Fig. 2; and

Fig. 6 is a fragmentaryview of the motor block corresponding to theportion thereof shown in Fig. 2 but illustrating an annular ring set inthe valve seat portion of the block, which portion is shown as cut outin Fig. 2 and said ring having a valve seat formed therein.

The motor block is indicated as an entirety by the numeral 7, thecylinders by the numerals 8, the valve opening by the numeral 9, valveseats by the numeral 10, and the valve stem guides by the numeral 11.The engine block is here illustrated with the cylinder head removed andthe cylinder head bolts, which are indicated by the numeral 12, projectconsiderably above the surface of the cylinder block proper and thecylinder head bolt nuts, which are illustrated as only being applied tothose cylinder head bolts, which are in use, are indicated by thenumeral 13.

My valve seat cutting device includes a cutting element or tool 14removably and adjustably carried by a chuck-like cutter head 15 that isformed on the lower end portion of a cutter spindle or arbor 16. Thisarbor 16 is rotatively mounted in a combined arbor supporting bearingand feed screw 17, which combined arbor supporting bearing and feedscrew is in the form of an externally threaded sleeve formed at itsupper end portion with an enlarged cuplike head 18 that is normallyclosed at its upper portion by means of a cap 19 that is removablysecured thereon by means of screw-threads 'or the like. The upper endportion of the arbor 16 is made angular at 16a for application of asuitable tool such as a wrench or the like, not shown, for turning thearbor and the cutting tool to form a cutting operation.

Detachably mounted on the upper end portion of the arbor, below theangular portion 16a, and cletachably secured thereto by frictionalengagement and contained within the cup-like upper end portion of thearbor supporting bearing 17, is a stop collar 20. The stop collar 20 isin the form of a split annular ring that is detachably and adjustablysecured on the arbor by frictional clamping action produced by means ofa clamping screw 21. This stop collar 20 is rotatable within thecup-like portion 18 and by engagement thereof with the bottom of saidcup-like portion 18 and the top of the cap 19, said arbor is adjustablyheld against axial movements through the supporting bearing 17 but isfree for rotation therein.

The combined arbor supporting bearing and feed-screw 17 is mounted inand has screwthreaded engagement with a ball-like member 22, the sidesof which are approximately semispherical and which member 22 forms theuniversally movable member of a ball and socket joint 23. The ball andsocket joint 23 comprises the ball-like member 22, an upper half socket24 formed on the inner approximately annular end of a mounting arm 25and. a lower half socket 26 formed on the inner approximately annularend of a mounting arm 27. Thesehalf sockets 24 and 26 are normally heldin loose frictional engagement and are adapted to be clamped tightlyagainst the semi-spherical surfaces of the ball-like member by means ofa retaining and clamping device comprising a collar 28 and clampingscrews 29. The collar 28 surrounds the ball and socket connection and isseated on the upper annular portion of the mounting arm 25 and thescrews 29 have screwthreaded engagement with the arm 27 but are entirelyfree from the arm 25. It should now be apparent that when the screws 29are loose, the ball-like member 22. combined bearing and feed screw 17and arbor 16 will be free for universal movements in respect to the arms25 and 27 and said arms will be free for pivotal movements in respect toeach other. When the 110.

screws 29 are tightened; however, the half sockets 24 and 26 will betightly clamped against the semi-spherical surfaces or" the ball-likemember 22 and thereby lock the bearing supporting sleeve 1'7 againstuniversal rocking movements in respect to the arms and said againstpivotal movement in respect to each other. The arms 25 and 27, which arequite heavy and very rigid, have flat bottom surfaces that are in thesame horizontal plane and which are adapted to be seated on the smoothflat top of the engine cylinder head and said arms are provided withlongitudinal slots 30 that are adapted to receive cylinder head bolts12.

The particular cutting element 14, here illustrated, is meant for thepurpose of cutting away the portion of the cylinder blocks surroundingthe valve opening 9 and in which portion the valve seat 10 is all formedsubstantially as illustrated in Fig. 2. When this cutting operation iscom plete an annular ring 31 is pressed into the cut-out portion andthen a new valve seat 16 is formed in said ring 31. This operation is,however, common practice in the automobile trade and when the operationis accurately done, highly satisfactory results are obtained. In orderto obtain a high degree of accuracy, however, it is first essential toaccurately position the cutting element before the cutting operation iscommenced and to positively hold the same positioned during the cuttingoperation.

Cooperating with the chuck-like cutter head '15 of the arbor 16 anddepending axially therefrom is a pilot stem 32, which stem 32 adapted tobe inserted into and closely engage the sides of the valve guide thatcooperates with the particular valve seat to be operated on toco-axially align the arbor 16 with the valve guide and thereby properlyposition the cutting element 14 at right angles to the valve guide. itis, of course, understood that a valve seat should always be in perfectaxial alignment with its cooperating valve guide and it is, therefore,essential in performing a cutting operation, as here illustrated, tohave the out perfectly round and centered in respect to said valveguide.

The cutting element 14 is adjustably and removably secured in thechuck-like cutter head 15 by means of a set-screw or the like 33 andsaid cutter 14 will be set before the cutting operation is commenced tomake a cut of the desired diameter.

Attention is now called to the fact that the arbor 16, which is heldagainst axial movements in respect to the combined feed-screw andsupporting bearing 17 is movable axially through the ball-like member 22with said combined bearing sleeve and feed-screw by screwing said sleeveupward or downward in respect to said ball. By this means the cuttingelement 14 may be set at a desired elevation and progressively moveddownward during the cutting operation to increase the depth of the cut.

Operation To set the device for a .cuttin operation the clamping screws29 are loosened sufficiently to release clamping action of the halfsockets on the ball-like member 22 and permit free universal movementsof the bearing sleeve 1'7 in the arbor l6 and free pivotal movements ofthe arms 25 and 2'7 in respect thereto and in respect to each other. Thearbor is now raised upward by screwing the combined bearing sleeve andfeed-screw upward to such an extent that the bottom of the cutter 14will be above the bottom of the arms 25 and 27. With this accomplishedthe pilot stem 32 may be inserted into the valve guide 11 of aparticular valve seat to be operated on and the arms 25 and 2'7 seatedagainst the engine block with the slots 30 in each thereof slipped overa conveniently located cylinder head bolt 12. The pilot stem 32, whichshould be of proper size to snugly fit the guide 11, will veryaccurately position the arbor 16 in coeaxial alignment with the guide 11and also position the cutter at right angles thereto. With the arbor 6properly aligned the cylinder head bolt nuts 13 may be applied to thebolts 12 and drawn down tightly against the tops of the arms 25 and 27and the clamping screws 29 are then tightened to cause the half sockets24 and 26 to tightly engage the ball-like member 22.

It will now be apparent that'the arbor 16 will be positively heldagainst 'wabbling movements in the pie-aligned position during thecomplete cutting operation even though quite great side thrust be.exerted thereon caused by turning pressure applied to the upper endportion of the arbor 16. The cutting element 14 should now be moveddownward by manipulation of the combined bearing and feed screw 17 sothat the bottom thereof engages the top of the blocks, as shown bydotted lines in Fig. 2. 1

By reference to Figs. 2 and 5, it will be seen that the feed screw 17 isprovided with an adjustable cut depth determining and limiting stopcollar 34, which collar is split and pro- 1 vided with a clamping screw35. has screw-threaded engagement with the feed screw 17 and has adepending skirt-like portion 36, the bottom of which is adapted toengage the annular stop projection 3'7 formed on the upper portion ofthe ball-like member 22. I With the cutting element 14 adjusted toengage the top of the block, as shown by dotted lines in Fig. 2 prior tothe commencing of the cutting This collar 34 1' operation, the depth ofthe cut to be made is determined and the cut depth and determining 1 andlimiting stop collar 34 is set so that the bottom of its skirt-likeportion 36 is spaced from the top of the annular stop projection of theball-like member 22 a distance equal to that of the depth of the outdesired.

supporting bearing 17.

This progressive downward movement will, of course, be continued untilthe skirt portion 36 of the cut depth determining and limiting stopcollar 34 comes into engagement with the stop shoulder 37 on theball-like member 22, at which 1% time the cut will be of thepredetermined depth and the operation complete. 7

It is obvious that the cylinder head bolts in various engines arelocated at much different positions relative to the valves and also that1 even in the same engine the cylinder head bolts will be located indiiferent relation to the various valves thereof, and it is, therefore,highly important that the mounting arms 25 I and 27 are movablepivotally in respect to one another and that they be provided with slotsor the like so that they may be brought into cooperation with boltslying at various distances from the Valve.

By reference to Fig. 1, it will be noted that in the event that theparticular cylinder head bolts 12, illustrated as being used to clampthe arms 25 and 27 against the top of the cylinder block were absent,the arms might be swung into the position, shown in dotted lines, tocooperate with other cylinder head bolts 12. It will appear from theabove that this device will be universally applicable to substantiallyall engines.

It is also important to note that the mounting arms 25 and 27 are alwaysat considerable angle to one another and therefore very rigidly bracethe supporting bearing sleeve.

What I claim is:

1. The combination with a tool for operating on valve seats comprising acutting element, an arbor for said element, and a pilot stem adapted tobe inserted into and closely engage a valve guide that cooperates withthe particular valve seat to be operated on and to cooperate with saidarbor to co-axially align the arbor with the valve guide, of an arborsupporting bearing in which said arbor is rotatably mounted, a pair ofmounting arms for said supporting bearing, a ball and socket connectionbetween said arms and said arbor supporting bearing comprisingsubstantially semi-spherical surfaces carried by said arbor supportingbearing, a lower half socket formed on one of said arms, and an upperhalf socket formed on the other of said arms, said arbor supportingbearing normally being free for universal movements in respect to bothsaid arms, and said arms being free for pivotal movements in respect toone another and said arbor supporting bearing, clamping means forpositively locking said semi-spherical surfaces against movement inrespect to said arms, and said arms against movement in respect to eachother and means for feeding the arbor through its supporting bearingincluding external screw feed threads on the supporting bearing.

2. The combination with a tool for operating on valve'seats comprising acutting element, an arbor for said element, a pilot adapted to cooperatewith the arbor and the valve stem guide of a particular valve seat to beoperated on to co-axially align the arbor with the valve stem guide, ofa combined arbor supporting bearing and feed-screw in the form of anexternally screw-threaded sleeve in which the arbor is rotatablymounted, means for holding said arbor against axial movements insaid'oombined sup porting bearing and feed-screw, mounting arms for saidcombined supporting bearing and feedscrew, 21. ball and socketconnection between said arms and said combined supporting bearing andfeed-screw comprising a substantially spherical member carried by andhaving screw-threaded engagement with the combined supporting bearingand feed-screw, a lower half socket formed on one of said arms and anupper half socket formed on the other of said arms, said combined arborsupporting bearing and feed-screw being normally free for universalmovements in respect to said arms, said arms being free for pivotalmovements in respect to each other, and means for positively lockingsaid semi-spherical surfaces against movements in respect to said arms,and said arms against movement in respect to each other.

FREDERICK W. SEELERT.

